If you have registered your Expo ID by yourself, you must set up your identity verification. If you have registered by proxy, you can use the service without setting it up, but setting it up will increase the security strength and allow you to use the following services:
・Purchase tickets
・Update your profile
・Change your password
etc.

https://www.expo2025.or.jp/wp/wp-content/themes/expo2025orjp_2022/assets/pdf/tickets-index/id_registration_manual_en.pdf